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Primes of the form 2^(2^n) + 427.
1

%I #7 Sep 08 2022 08:46:17

%S 431,443,683,65963,4294967723

%N Primes of the form 2^(2^n) + 427.

%C Terms given correspond to n = 1, 2, 3, 4 and 5.

%C Next term >= 2^2^27 + 427. - _Charles R Greathouse IV_, Jun 07 2016

%t Select[Table[2^(2^n) + 427, {n, 0, 15}], PrimeQ]

%o (Magma) [a: n in [0..16] | IsPrime(a) where a is 2^(2^n)+427];

%o (PARI) for(n=1,5, if(ispseudoprime(t=2^2^n+427), print1(t", "))) \\ _Charles R Greathouse IV_, Jun 07 2016

%Y Cf. similar sequences listed in A273547.

%K nonn

%O 1,1

%A _Vincenzo Librandi_, Jun 02 2016